1. Field of the Invention
This invention relates to a connector, and more particularly to a connector which is suitably used under vacuum environment.
2. Description of the Related Art
Conventionally, there has been proposed a connector that is comprised of an insulating material (housing), holding clips, and socket contacts (see Japanese Laid-Open Patent Publication (Kokai) No. S62-131485 (page 3, lower left column, line 6 to upper right column, line 1; FIG. 1).
The insulating material is formed with a plurality of cavities. The cavities are spaces having a generally cylindrical shape, and each have a small-diameter portion, a large-diameter portion, and a medium-diameter portion. The small-diameter portion is located at an end of the housing toward a mating connector. The medium-diameter portion is located at an end of the housing opposite from the end toward the mating connector. The large-diameter portion is located between the small-diameter portion and the medium-diameter portion.
Each holding clip has a generally hollow cylindrical shape, and is made of an elastic material. The holding clip has an outer peripheral surface formed with a pair of spring pieces opposed to each other. The pair of spring pieces are cantilevered, and the distance therebetween becomes shorter toward foremost ends (free ends) thereof. Further, the outer peripheral surface of the holding clip is formed with a slit parallel to the central axis of the holding clip. When the holding clip is radially urged, the width of the slit is reduced to reduce the outer diameter of the holding clip.
Each socket contact has a shape in which three cylinders having different outer diameters are continuous in a line.
This connector is assembled as follows:
First, the outer diameter of the holding clip is reduced, and in this state, the holding clip is inserted into the large-diameter portion of one of the cavities of the housing via the medium-diameter portion thereof. The outer diameter of the holding clip inserted into the large-diameter portion returns to its original state to bring the holding clip into intimate contact with the inner surface of the large-diameter portion.
Then, the socket contact is inserted into the small-diameter portion and the large-diameter portion via the medium-diameter portion. The socket contact inserted into the small-diameter portion and the large-diameter portion is engaged with the spring pieces of the holding clip, which inhibits the socket contact from being drawn out from the cavity.
On the other hand, when it is necessary to disassemble the connector e.g. for repair, a hollow cylindrical jig is inserted between the spring pieces of the holding clip and the socket contact to disengage the spring pieces and the socket contact from each other. This makes it possible to draw out the contact from the housing.
In the above-described connector, when the connector is disassembled e.g. for repair, it is possible to draw out the socket contact from the housing, but it is impossible to draw out the holding clips therefrom. Therefore, when one of the holding clips and the housing is damaged or broken, which requires replacement thereof, it becomes necessary to replace both the holding clip and the housing.
If the holding clip has to be drawn out from the housing, it is necessary to break a portion of the housing defining a third hole therein.
In a connector used in the atmosphere, an inexpensive resin can be used as a material of the housing, and the holding clips are manufactured at low costs. Therefore, even if both the holding clip and the housing are replaced, it cannot cause a serious problem.
Recently, the use of connectors has been widened, and there exists a connector that is used in a vacuum. Although the connector used in a vacuum has the same construction as that of the above-described connector, ceramic is used as a material of a housing thereof so as to prevent occurrence of out-gassing from the housing.
Also in the connector used in a vacuum, when it becomes necessary to replace damaged holding clips, the holding clips are replaced together with the housing of the connector.
However, since the ceramic housing of the connector used in a vacuum is very expensive, it is uneconomical to replace the damaged holding clips together with the housing that is not damaged.